There can be little doubt that 2018 will go down in the record books as the worst year in Ontario for dealing with ear mould in corn and contamination by deoxynivalenol (DON). Wet weather through silking and then again in much of October and November challenged growers getting into their fields for timely harvesting of their corn crops, and what followed only added to their frustrations: waiting in line at the elevator to see whether their loads would be acceptable.

Now, the outcome is well known and most growers are just glad to see 2018 in their rear-view mirrors.

What’s unsettling is that last fall wasn’t a case of a perfect storm of weather conditions and disease inoculum. Worse, there are indications the problem has yet to peak.

It’s what many had feared. The corn sector has fallen behind in dealing with ear rot diseases at that same time those outbreaks have worsened.

The numbers are obvious

Looking at the figures compiled by the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA), there is little doubt about 2018 and DON concentrations (see Table 1 below). At the 2019 FarmSmart conference in Guelph, Albert Tenuta and Dr. David Hooker made a presentation that included 2018 OMAFRA survey data.

On their own, the numbers are disturbing, particularly the double-digit figures on DON concentrations of greater than 5.0 parts per million (ppm), which makes the grain unsuitable for use in diets for cattle and poultry (see Table 2 below). When the data are compared with the seven previous years, however, the message is clear: 2018 really was the worst year to date for ear mould and subsequent DON concentrations.

One added revelation is that a pattern is beginning to emerge from the past eight years. Yes, 2018 was bad, but 2017, 2016 and 2011 were also tough years when looking at DON concentrations greater than five ppm. And 2006 had approached the severity of last year.

According to Tenuta, growers might consider the impact of 2018 and relax, believing 2019 can’t possibly see a repeat of the conditions that caused so much grief for farmers and the industry. But with four of the past eight years having DON issues, it’s a growing problem. Tenuta notes there are hot spots each year in parts of Ontario: the difference between 2018 and other problem years is that these areas have a larger geographical footprint.

“Whenever we have these big epidemic years, it is always centred around southwestern Ontario,” says Tenuta, field crops pathologist with OMAFRA. “It’s because there are a lot of acres. Whether it’s corn or wheat, that’s the primary production area of the province. If they’re affected significantly, then the province is affected significantly.”

Wheat’s ahead of corn?

Corn and wheat actually share a connection in the mould-and-blight picture in the region since gibberella ear mould (GER) and fusarium head blight (FHB) are caused by the same fungal pathogen, Fusarium graminearum. In corn, GER is named after the sexual stage of the pathogen, Gibberella zeae.

Nomenclature aside, Tenuta notes that in the past five to seven years, the wheat sector has had several fusarium head blight hot spots but they haven’t had the same impact previously observed.

“That tells the story of where the two industries have been moving,” says Tenuta. “It’s the same pathogen but the wheat sector is moving towards creating more tolerant wheat varieties, and more importantly, removing more of those really susceptible varieties from availability to the producers. So we’re planting fewer acres of those susceptible wheat varieties and we’re seeing the development of more and better fungicides that target fusarium head blight.”

A third pillar for wheat is in researching optimal timing for fungicide applications, including the development of the DONcast model, and all of these management tools or strategies have helped reduce the overall risk in some years while decreasing severe losses.

“When we look at the corn side — and 2018 is a great example — we had some high-yielding corn hybrids that were very susceptible to gibberella and DON production, and those hybrids covered a lot of acres in the southwest,” says Tenuta. “Unfortunately, it’s going back to the management decisions by the producers and in many cases, they’re starting to select fewer hybrids for their farm and in doing so, you’re decreasing the diversity on your farm and potentially increasing your risk, as well.”

High turnover on hybrids

That trend presents additional challenges to the grower given the rate of turnover of hybrids together with the focus on yield and on weed and insect resistance by the seed and breeding sector. Yet a silver lining may be that 2018 has reset the focus on diseases.

“Gibberella isn’t a major issue every year and with some of the newer hybrids, we don’t know enough about the level of tolerance amongst the majority of hybrids,” says Leanne Freitag, agronomic services support manager with Syngenta Canada. “There are a few that stand out one way or another, especially in years like 2018, but it can be hard to get a handle on them because of a lot of hybrids don’t last more than a few years, and during that time, DON might not be an issue.”

Some hybrids have been growing for three to five years, during growing seasons when ear rots weren’t an issue, or at the very least, weren’t an issue in those identified hot spots. But in 2018, says Freitag, multiple factors combined and led to a severe outbreak whose effects were devastating to some.

Although planting date wasn’t a direct cause of the epidemic, weather conditions occurred at the right time to infect — i.e. when silks were emerging, causing high levels of infection in several areas. Then the weather conditions during grain-fill were conducive for infection to progress and thrive.

Breeding and selecting for disease resistance is a difficult process, reminds Freitag, adding that the main focus of researchers and breeders in recent history has been on yield and insect resistance. And that tightened focus is shifting as diseases like gibberella or even penicillium and diplodia ear rots become more prevalent.

“Breeders are putting more focus on breeding and selecting for higher tolerance of DON and gibberella but a hybrid still has to be brought all the way up to the commercial level and perform well in the field,” says Freitag.

Increasing aggression?

Freitag has also heard of a disturbing trend that was outlined earlier this year by Dr. Pierce Paul from Ohio State University, who reported that there are two main DON pathogens in corn.

“One is much more aggressive, in that it has a higher ability to produce more disease and more mycotoxins,” says Freitag. According to Paul, 20 years ago, the more aggressive DON represented only three per cent of the pathogen population in corn and the less aggressive represented 93 per cent. A decade later, it had shifted so the more aggressive one represented 44 per cent and the less aggressive was at 56 per cent.

Freitag hasn’t heard what’s happened in the past 10 years but given the progression from the late 1990s to the late 2000s, it stands to reason that the more aggressive pathogen would occupy a greater percentage. And that may be why DON has increased in frequency.

As for dealing with the disease, both Freitag and Tenuta recognize there are strategies that already exist. Freitag points to livestock producers, particularly those in the hog sector, who have worked to understand which hybrids are susceptible and which have better tolerance.

As well, from an agronomic standpoint, working with plant populations, row widths and minimizing plant variability — by conducting proper planter maintenance and monitoring planting speeds to promote more uniform emergence — are all keys to managing risks. Good soil fertility is another fundamental that will help mitigate stress, as well.

Of course, the weather always has the final say.

For Tenuta, management comes with accepting that diseases like gibberella are now a common fact of life for growers. But they also can’t assume that by applying a fungicide, they’re getting ear rot control, which may not be the case.

Fungicide applications pertain to two purposes: for foliar diseases at that tassel or pre-silk timing, and as a method of improving plant health. Neither targets ear rots.

“Just because a grower has applied a fungicide does not necessarily mean they’re getting the benefit of an ear rot or DON reduction,” says Tenuta. “You have to be targeting the silks and the timing, and you need a prothioconazole or metconazole product to help on the gibberella and DON side, as well.”

For growers in the Great Lakes region of Ontario, gibberella ear rot should be one of the highest priorities in corn production, adds Tenuta.

“We have inoculum all around for wheat and corn, ” Tenuta says. “It’s not a limiting factor.”

It’s never been easy to be a farmer, but now it’s even more complicated. Just add up the risks: skyrocketing land and equipment prices, increasingly demanding consumers, tightening markets, unreliable weather, growing trade uncertainty…

Meanwhile, government agriculture research and extension dollars dwindle, leaving farmers more on their own to figure out how to respond to changing agronomic and business pressures.

Luckily, farmers, by nature or necessity, tend to be resilient and adaptable. That’s why tomorrow’s best farmers will be adding on-farm research to their regular to-do lists.

“Yes, farmers can — and really they should — conduct research on their own farms,” says Catherine Tarasoff, a crop scientist and the author of the Guide to On-Farm Demonstration Research, a how-to manual for farmers released by the B.C. Forage Council.

“There’s a real misconception that research has to be complicated, meticulous and technical to be good; that it is overwhelmingly difficult or time-consuming. That isn’t the case at all,” Tarasoff says. “All you need to do to conduct a successful on-farm research project is to ask one question and then figure out a simple way to measure results to find an answer to that question. That’s it.”

While on-farm research is not as rigorously tested, replicated and analyzed as laboratory-style research, its results can still be applicable and useful to an individual farm. Country Guide sat down with Tarasoff to get a quick primer on how to conduct on-farm research in any farm type or scale.

Start with your goals

Let’s call a spade a spade: an on-farm research project will demand time and effort, but it can have a positive return on investment. To achieve that, you first need to identify your personal goals and priorities — the 10,000-foot reasons that shape your business.

“Goals are a simple summary of ‘why’ but do not get into any details surrounding ‘how,’” explains Tarasoff.

Divide a piece of paper into three columns. In the first, write a list of the general, biggest-picture improvements you’d like to see. In the second, write a list of your farm and personal priorities. In the third, write a list of your business resources, opportunities and limitations.

Then look at your first column and consider how well each improvement aligns with columns two and three. If you wrote down “maximize profits” in column one but column two’s highest priority is “improved work-life balance,” your farm will gain no value from a project that tests a time-sucking intensive-management technique. However, it might gain value from a project that tests nitrogen efficiency.

Each on-farm research project should be designed to address a single goal. All businesses are built around multiple priorities, but an on-farm research project’s success hinges on it being simple, low-cost and manageable, and on its answers being clear and obvious. If your goal is to make more money, don’t muddy it and reduce your chance of success by also trying to include sustainability or other take-aways within the same project.

Farm plot trials may need to be larger than commercial trials, and cover a large enough representative area that can be managed using farm-scale machinery.photo: Supplied

“You do not need to answer everything in one research effort,” says Tarasoff. “Don’t get overwhelmed. Small and precise does not mean insignificant. Results are powerful and informative, even if your question was small — probably especially if your question was small.”

Once you have determined your goal, drill down into objectives. For example, if your priority is to improve environmental sustainability, an objective might be to reduce fertilizer usage by X per cent.

Start making your plan

Once you have identified a specific goal, it’s time to create a road map.

While most farmers prefer “productive” work and find the planning stage of a research project onerous and slow, it’s important to take the time at your kitchen table to detail the specifics of your project.

Start by brainstorming a list of questions. For example, if your goal is to increase profits and your objectives are to decrease fertilizer use and increase yields, you might ask:

• What are ideal varieties for my specific soil type?
• What fertilizer rates do I need for optimal production?
• Will new variety X offer better returns?

Look at your list and identify which question, if answered, would offer the greatest return. Then, consider whether those questions need complicated or simple testing. Remember, simplicity is key.

“A concise, focused experiment that looks to answer a yes/no or an A versus B question is the most likely to be successful,” says Tarasoff.

“You don’t need to measure everything. If you’re interested in yield, don’t measure soil microbes. Focus only on what you need to determine to answer your specific question.”

Then, carefully analyze the “how” of your experiment. A project’s success hinges on choosing a design that will work, not just in theory but in the practical reality of your farm business.

“You may come up with the perfect question and the ideal way of measuring for that question, but if the measurements need to be taken at your busiest time of year, your design may not be realistic,” says Tarasoff.

Figure out the details

Be realistic about what the proposed project will require, and then be pragmatic about whether your farm can comfortably carry that outlay. If a project uncomfortably stretches your resources, consider trying to achieve that goal via a different, less investment-heavy angle. Remember: simple is better.

“A good on-farm research project should require no specialized equipment beyond minor things like a kitchen scale or paper bags,” says Tarasoff.

In this stage, you need to draw maps, consider details, and get ultra-specific in your planning. Focus on designing your project to minimize outside factors that could skew your results. If your project is to optimize fertilizer rates, for example, choose an average representative location for your farm.

Tarasoff also recommends these steps:

1. Consider access and any features within the proposed project area.
2. Consider long-term operations: could this project affect long-term use of the proposed test site?
3. Identify and then plan to avoid edges, anomalies, and travel-through areas.
4. Ensure there is room for equipment.
5. Go fairly big: in order to ensure natural variation is averaged out, test over a decently large area. A forage producer, for example, should test a swath about 500 feet long. A fruit producer should test multiple trees.

Now, map it. Working to scale, identify all reference features including which areas to avoid. Think through how you will delineate the edges of your test plot: your results will only be as good as the data you put in.

Ideally (and depending on the project), plan for two passes of any equipment to ensure any equipment inconsistences are taken into account.

Roll it out!

Be ready for pitfalls, roadblocks and unexpected research turns. As Tarasoff says, the only certainty in research is uncertainty. In order to maximize the value of your efforts, be ready to make changes and adjustments on the fly. This may require modifying your research question and/or analyzing or adjusting your measurements should a variable appear.

“In research, things always go sideways. If you don’t have a good idea of exactly why you’re doing it, it’s hard to salvage. If you have a good plan, it’s easier to get some value even when your project doesn’t go the way you planned,” says Tarasoff. “Don’t worry about what could have been. Do what you can to capture value with what you’ve got.”

Collect your data

If you apply a treatment to a significant area, testing the whole population’s response would be impossible. For example, if you apply one rate of fertilizer to half a field of alfalfa and another rate to the other half, sampling every plant’s response would take forever. Instead, you need to sample enough plants and the right plants to get a true representation of the total population.

“It is a really hard thing to choose an accurate sample,” says Tarasoff. “The challenge is stopping your brain from looking for the result you expect. Your eyes will find what your mind wants them to. Don’t look for the best, healthiest plants or avoid the ones that don’t fit your notion of how the experiment was supposed to turn out.”

Instead, she recommends finding a technique that forces you to take a completely random sample. If sampling a wheat field, for example, she suggests using a hula hoop to outline a sample area and then collecting every plant inside that hoop.

Remember that variability exists everywhere. Depending on the project, farmers may have the option to avoid patches/sites that are particularly variable. As Tarasoff says, “Why introduce high levels of variability if you can avoid them?”

“To minimize the impact of variability on your final results, sample enough of the population to dilute outlier data, repeat the experiment as often as possible (repetition confirms and builds confidence in the results), and — most importantly — design your project to offer strong enough results that subtle variability doesn’t matter,” says Tarasoff.

Analyze your results

You made your plan; you carried it out; now you have a collection of raw data. So far, so good. But you’re not home-free yet. Don’t guess or base your answers on a quick visual estimate. Instead, actively analyze those results to determine how much of an impact your tested treatment makes. In many cases, analysis is as simple as inputting numbers into a spreadsheet. Let the numbers speak for themselves.

What if there is no difference in your research results? For example, if you test two fertilizers and see no yield difference at all, are your efforts of no value? “There’s always a difference!” says Tarasoff. “It might not be the difference you expected, but there’s always a difference. Sometimes you just have to look at the answers differently.” For example, maybe the difference comes down to price, ease of use, or timing: factors that provide unintended benefits.

Put that research to work!

While research has long been considered a complicated task only achievable by scientists, research is actually anything that improves one’s understanding of the world around you.

“Think of a little kid, lying in the grass and looking through a magnifying glass at an insect,” says Tarasoff. Once he knows, from hands-on experience, that the bug he’s looking at has six legs, he’ll never make the mistake of thinking it might just have four. That’s research, and it’s just as authentic and valuable a form of research as anything conducted in a lab.”